My laptop has been doing this for years, when I press the screen switch (from int to ext) an image is still displayed on the LCD, albeit very faint and only visible from certain angles. It's not just burn either, the image does change as it should but according to the instructions and diagnostic no power is flowing to the screen! Magic!

(Note: I obviously do not believe the diagnostic tools supplied with the laptop and am fully aware that this is not "spiderwebs and magic")

Since the technology isn't specified it is hard to say whether it is a real step forward, but retaining an image on a LCD panel is nothing new. Thorn EMI's Central Research Laboratories developed a colour Ferro electric LCD (FLCD) in the early 1990s (1992?) that would do exactly that. FLCD panels will retain the image indefinitely without power being applied (although power is still required for the backlight to view the image).

... let me get this right - a screen that retains its image after power-down, but is actually drawing large amounts of power to keep it retained?

So what you're saying is that it has an off button, that doesn't actually do anything.

Worst . . . product . . . announcement . . . everrrr.

.

In all seriousness, even if it could retain the LCD image without power, that large power consumption is actually going towards the CCFL backlight - has anybody ever seen a fully functional screen but with a broken or otherwise 'off' CCFL? You get nothing useful.

Furthermore the argument for LCD eInk is pointless, the point of current eInk tech is that it doesn't emit any light. You know, kind of like how your common or garden book works! LCDs on the other hand...

...that is unless you're talking about the same kind of LCD screens you get today in some alarm clocks, watches, or those cool 1980s monochrome LCD videogames, which have always had really dull contrast.

I remember seeing this exact kind of thing on Tomorrows World (given thats been off the air for donkeys years...), it was a special with Prince Charles, same episode had 1 way posters for shop windows (so shoppers could see out of the shop & let in light, but looking inwards it looked like a normal poster).

... you can still see what you were working on just before the power went?

Worst. Product. Ever.

On the other hand.... if surfing the web,and bashing the bishop, this could be a climax saver!

Mines the one with the UPS in the pocket.

"The LCD panel's operational temperature ranges from -25 to +55°C. So, its use is limited to indoors at this moment. "

Mine's the fur-lined one with the hood, heavy gloves and boots.

Thorn EMI CRL were finalists one year in the annual Prince of Wales award thingy that Tomorrows World used to do.

... to enlighten the likes of Stu as well, FLCDs are used in certain niche markets, and draw no current with a static image. The smectic FLC is used in most of the microdisplays, and can switch state faster than the usual nematic LCs used in TFTs. I haven't had a chance to check the tech being shown off by Sharp, but it could be they have overcome the thin-film requirements for smectic FLCs (which is why they aren't used in TFTs).

It's not magic. The front button only cuts off power to the backlight, not the entire panel :P

"has anybody ever seen a fully functional screen but with a broken or otherwise 'off' CCFL?"

No, I've never seen anything "FULLY FUNCTIONAL" that has any part of it not work. I'm pretty sure that means it isn't fully functional.

Anyhow, if someone could invent better backlight technology and do away with it *properly* without any negative side effects, and improve black depth that's be great. I'm not sure I need the image once the screen is off.

So, the panel requires a burst of energy to "save" the image but no more thereafter to preserve it. Methinks a capacitor is being charged somewhere and is being used to power a relatively classic LCD albeit maybe with reduced power consumption.

I'm sure in the past I've seen LCD tech that has the option to not use a backlight, but instead open the back of the panel to sunlight and use that instead

I think I also remember a system before the advent of cheap projectors that let you detach the lid of the laptop, remove the back of the panel and sit it on an old fashioned OHP and project onto a screen that way.

Maybe someone should bring back the screen-with-no-back idea and sell it as environmentally friendly... the greenies would love it, sales would surge on a tide of green nonsense